（23）語態和語氣
Ⅰ. 語態
1. 動詞的語態有兩種，一種是主動語態（Active Voice），另一種是被動語態（Passive Voice）。
主動語態是以句中的主語為主動的，而被動語態就是以那主語為動作的對象的，例如：
① A dog bit the boy.（Active Voice）
狗咬了小孩。
② The boy was bitten by a dog.（Passive Voice）
小孩被狗咬了。
大部分的情形是可以把語態互相改寫的，只有極少數的動詞，如 happen 等，才沒有被動語態。
2. 由主動改成被動時，是要把原來的賓語用作主語，而動詞就用 be + Past Participle 的形式，然后加 by，再加賓語（即原來的主語）。
3. 主動改被動應注意下列各項：
a. 用 people，they，you，we，one 為主動語態的主語，而指一般人的場合，改作被動語態時，通常將這主語略去，不必再加 by people 的字樣：
People say that he is rich.（Active）
It is said that he is rich.（Passive）
They speak English all over the world.（A）
English is spoken all over the world.（P）
What do you call this flower？（A）
What is this flower called？（P）
One does not feel a burden of one’s own choice.（A）
A burden of one’s own choice is not felt.（P）
b. 如有兩個賓語的話，被動就有兩種寫法：
He gave me this advice.（A）
I was given this advice by him.（P）
This advice was given me by him.（P）
c. 帶有介詞的動詞，改為被動時，介詞仍不可少：
They take care of him.（A）
He is taken care of by them.（P）
She laughed at me.（A）
I was laughed at by her.（P）
We sent for the doctor.（A）
The doctor was sent for.（P）
d. 命令法的場合，要加用 let 一詞：
Do it at once.（A）
Let it be done at once.（P）
Take this letter to the post-office.（A）
Let this letter be taken to the post-office.（P）
e. 動詞為 know 的時候，后不接 by，而要接 to：
Everybody knows him.（A）
He is known to everybody.（P）
f. 動詞的數及時態，應隨之改變：
Virtue makes life happy.（A）
Life is made happy by virtue.（P）
I will pay the money.（A）
The money shall be paid by me.（P）
I shall pay the money.（A）
The money will be paid by me.（P）
They can not have said such a thing.（A）
Such a thing can not have been said.（P）
g. 有時中國話說的主動語態，英文卻要用被動語態：
I am delighted to see you in good health.
I was surprised at his ignorance.
I am interested in learning English.
I am satisfied with the result.
I was disappointed then.
The train was derailed near Taipei.
（注）被動語態不一定要用 by，如果是指工具就要用 with，只有指行為者才用 by，例如：
He was killed by the robber.
He was killed with a sword.
Ⅱ. 語氣
1. 動詞的語氣有三種，即直陳語氣（Indicative Mood），祈使語氣（Imperative Mood）和虛擬語氣（Subjunctive Mood）。
2. 直陳語氣是不問現在、過去、未來而只是直述某種事實的，一般普通的語句，大都是用的這種語氣。
He studies hard.
He is very diligent.
Dead man tells no tales.
What is the best formula for success in life？
3. 祈使語氣是用于表示命令、請求、祈禱等的，普通常將主語的 you 省略不說，而動詞就用 Root form，否定句時則在動詞前加 do not 或 don’t 字樣。
Boys，be ambitious！（命令）
Bring me some water，please.（請求）
Lead us not into temptation，but deliver us from evil.（祈禱）
否定時則可說：
Do not sleep in the classroom.
Don’t yawn before others.
有時在普通動詞的 Root form 前再加上一個 do 字以加強語氣，如
Do save us！
對第一人稱及第三人稱的祈使語氣，就是用 let：
Let me go！
Let him do it！
Let us take a walk！
4. 在祈使語氣之后，接有 and 或 or 時，就是表示條件的。
Sow virtue，and the harvest will be virtue.（= If you sow virtue，then the harvest will be virtue.）
Keep quiet，or I will punish you.（= If you do not keep quiet，I will punish you.）（= Unless you keep quiet，I will punish you.）
5. 祈使語氣有時可用來表示讓步。
Be the work what it may，always do your best.（= Whatever the work may be，...）（= No matter what the work may be，...）（= Let the work be what it may，...）
Try as you may，you will not be able to master English in a few months.（= However hard you may try，you will not...）
Call when you will，you will find him out.（= whenever you may call，you...）
6. 將 suppose 和 say 用于祈使語氣時，則 suppose 當 if 解，say 當 for instance 解，例如：
Suppose you were in his place what would you do？
What do you say to going there in a week or so，say next Sunday？
7. 虛擬語氣的時態有四種，Present 用 If I be；Future 用 If I should be；Past 用 If I were；Past Perfect 用 If I had been。
8. Present Subjunctive（虛擬語氣的現在），表示對現在或未來的不確實的想象，第三人稱單數不加 s。
If he be good-mannered，he may also be good-natured.
（注）若將上句 Present Subjunctive 改為 Present Indicative 時，則成 If he is good-mannered，he is not good-natured. 在虛擬語氣的說法，意為“他的儀容好不好”尚不確實，若是“儀容很好的話，其性情可能也是好的”，不妨作此想象。至于直陳語氣的說法，則對“他儀容之好”已無疑義，而斷定“他儀容雖好，性情卻不好”。一則說的想象，一則說的事實。目下英美的口語，頗有以 Present Indicative 代替 Present Subjunctive 的傾向。
9. Future Subjunctive（虛擬語氣的將來），表示對現在或未來的強大的疑義。不論是何人稱，都用 should + Root 的形式，意為“萬一的話”，后接 should，would + Root 或 will，shall + Root 或命令句。
If he should be found older than I think，I would not employ him.（I don’t think he is old.）
If I should fail，I would try again.（I shall not fail.）
If it should rain tomorrow，the swimming meet will be postponed.
（注）第一句是對現在的，第二、三句是對未來的強大的疑義。
10. Past Subjunctive（虛擬語氣的過去），表示與現在的事實相反的假設，動詞常用過去式，但動詞 be 則要用 were，三個人稱都是一樣。后接的主句中的動詞，就要用 should（或 would，或 could）+ Root。
If I were rich，I could do so.（= As I am not rich，I can not do so.）
If I were you，I would go abroad.（= As I am not you，I do not go abroad.）
If he were with us，we should be delighted.（= As he is not with us，we are sorry.）
If it were not for the sun，we could not live at all.（= As there is the sun，we can live.）
11. Past Perfect Subjunctive（虛擬語氣的過去完成），表示與過去的事實相反的想象，動詞用 Past Perfect，后接 would，should + have + Past Participle 的形式。
If he had been diligent，he would have passed the entrance examination.（= As he was not diligent，he did not pass the entrance examination.）
If I had had money，I would have helped you.（= As I had no money then，I could not help you.）
If it had been fine，I should have been glad.（= As it was not fine，I was sorry.）
If it had not been for your help，I should have been drowned.（= As you helped me，I was not drowned.）
12. 除以上四種虛擬語氣之外，還有一些在語句中須用或代替虛擬語氣的地方，現分條舉出如下：
a. 表示與未來的事實相反的想象。如大家都知道陽光是永遠不會消逝的，現若假定太陽無光的話，就要用 If + were to 的形式，后接 should，would + Root。例如：
If the sun were to be extinguished，the whole earth would be fast bound in a frost in a day or two.
If I were to go abroad，I would go to America.
b. 在 wish 后面應該用虛擬語氣的 Past 或 Past Perfect，表示對于現在，過去將來的事難以達到的愿望。
I wish I were a musician.（= I am sorry that I am not a musician.）（現在）
I wish I had been there.（= I am sorry I was not there.）（過去）
I wish he could come.（= I am sorry he will not come.）（將來）
I wish to be a sailor.（將來的志愿）
I wish I were a bird.（現在未達成的志愿）
I wish I had been a statesman.（過去未達成的志愿）
I wish the rain would stop tomorrow.（將來的切望）
c. 在 as if 后應該接虛擬語氣，由 as if 引導的從句，不論主語的單復，常要用復數形。
He speaks as if he were my friend.（= He speaks as he would speak if he were my friend.）
He looks as if nothing had happened.
d. 省略 if 的場合。要將主語和助動詞或基本助動詞顛倒。
Were I rich（= If I were rich），I would buy it.
We may lie down there，should we fall ill.（= if we should fall ill.）
Were it not for freezing（= If it were not for freezing），the stars would not be so bright.
Had you been more careful（= If you had been more careful），you would not have fallen ill.
Had it not been for your advice（= If you had not given me your advice），I should have grown desperate.
e. 在虛擬語氣中用 would 的話，表示那主語有“肯做不肯做，原不知道，如果肯做的話”之意。
If you would only do your best，you would be sure to succeed.
If you would lend me the book，I should be much obliged.
但是如下的說法，又可以表示與現在相反的事實：
He could do it，if he would.
f. 用 Infinitive 來表示虛擬語氣的：
It would be wrong to tell a lie.（= It would be wrong if I were to tell a lie.）
I should be happy to be of service to you.
g. 用 Preposition 來表示虛擬語氣的：
I would go abroad，but for my poverty.（Were it not for my poverty，I would go abroad.）
Without water the plants and trees would all die.（= If there were no water，the plants...）
With an army of such soldiers，I could conquer the whole world.
h. 用 Conjunction 來表示虛擬語氣的：
He worked very hard，otherwise（or else）he would have failed.（= If he had not worked hard，he would have failed.）
Life would be short，but that hope prolongs it.
i. 用 Noun 來表示虛擬語氣的：
A wise man would not do such a thing.（= If he were a wise man，he would not do such a thing.）
j. 將條件句省略的場合：
I should like to go with you.（= I should like to go with you，if I could.）
He must be over fifty，I should think.（= He must be over fifty，I should think if I were to think about it.）
I could have come last evening.（= I could have come last evening if I had wanted to.）
Would you kindly lend me your pen？（= Would you kindly lend me your pen，if I were to ask you.）
Might I as k you to show me the way？（= Might I ask you to show me the way，if you didn’t mind.）
Could you spare me a copy？（= Could you spare me a copy，if I were to ask you.）